At present, domestic operators respectively establishes networks, which are all mutually independent from access network, metropolitan area network to backbone network. If a client of Operator A intends to access resources of servers of Operator B, he needs to pass through a uniform access channel between the network of the Operator A and the network of the Operator B. A switching center is included in the access channel. Any traffic from Operator A actively accessing Operator B and any traffic from Operator B actively accessing Operator A is counted at the switching center in the access channel. Thus any cross-network traffic is counted and can be billed accordingly. However, some unscrupulous users may try to avoid being billed for cross-network traffic.